Oilpan: move WebPluginLoadObserver to the heap.

third_party/WebKit/Source/web/WebDataSourceImpl.cpp

Index: third_party/WebKit/Source/web/WebDataSourceImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebDataSourceImpl.cpp b/third_party/WebKit/Source/web/WebDataSourceImpl.cpp
index 4b7bbd809aaca47d0c081cdfee0d344e455127a2..45a6748dec84a5747da2f73d56e0d989e9fbef60 100644
--- a/third_party/WebKit/Source/web/WebDataSourceImpl.cpp
+++ b/third_party/WebKit/Source/web/WebDataSourceImpl.cpp
@@ -38,9 +38,9 @@
 
 namespace blink {
 
-static OwnPtr<WebPluginLoadObserver>& nextPluginLoadObserver()
+static OwnPtrWillBePersistent<WebPluginLoadObserver>& nextPluginLoadObserver()
 {
-    DEFINE_STATIC_LOCAL(OwnPtr<WebPluginLoadObserver>, nextPluginLoadObserver, ());
+    DEFINE_STATIC_LOCAL(OwnPtrWillBePersistent<WebPluginLoadObserver>, nextPluginLoadObserver, ());
     return nextPluginLoadObserver;
 }
 
@@ -137,7 +137,7 @@ WebNavigationType WebDataSourceImpl::toWebNavigationType(NavigationType type)
     }
 }
 
-void WebDataSourceImpl::setNextPluginLoadObserver(PassOwnPtr<WebPluginLoadObserver> observer)
+void WebDataSourceImpl::setNextPluginLoadObserver(PassOwnPtrWillBeRawPtr<WebPluginLoadObserver> observer)
 {
     nextPluginLoadObserver() = observer;
 }
@@ -175,6 +175,7 @@ void WebDataSourceImpl::detachFromFrame()
 
 DEFINE_TRACE(WebDataSourceImpl)
 {
+    visitor->trace(m_pluginLoadObserver);
     DocumentLoader::trace(visitor);
 }